The invention concerns an apparatus for the extrusion of flowable masses from a cylindrical, rotating container which is provided with peripherally distributed passages for the mass. The mass is fed axially into the container, which is located above a conveyor, cooling belt or the like, upon which the extruding mass will drop and then solidify or gelate. The extrusion is brought about by a rotation of additional cylindrical bodies relative to the container.
Apparatus for the extrusion of flowable masses are known. For example, the published German patent application No. 10 85 139 discloses a design for the forming of a granulate where a plunger reciprocates inside a cylinder, with the mass being extruded from a set of nozzles located within a front wall of the cylinder, either in strip or drop form. Systems of this type are suitable for the processing of synthetic powders; these known arrangements are also equipped with heating devices.
Published German patent application No. 26 35 147 discloses another design for the manufacture of solid particles where a membrane, reciprocating under the alternating pressure of a fluid, extrudes the flowable mass from a number of nozzles. This specific design has the advantage that there is no need to arrange and move mechanical parts close to the walls of the chamber which contains the mass to be processed so that wear and tear can be held to a minimum. However, designs of this type are not very suitable for the processing of materials which will not readily form drops.
There are further known arrangements of the type discussed above (e.g., published German patent applications No. 17 67 381 and No. 12 87 045) where there is provided a rotating drum which carries passages, distributed over its circumference, into which is fed laterally the material to be granulated. The material is subsequently extruded from two diametrically opposed sides of the rotating drum by means of rollers which are fixedly but rotatably arranged inside the drum, their outer contours being in contact with the inner wall of the rotating drum. The granulate is then produced by means of cutting knives which are located at the outer surface of the rotating drum and which separate the extruding material into sections of desired length. Systems of this type have the disadvantage that wear and tear will occur at the points of contact between the inside rollers and the inner diameter of the rotating drum. Another disadvantage is due to the fact that devices of this type cannot be used to form granulates from very fluid materials which will extrude under pressure from the passages in the form of drops because such drops would then form at and across the entire circumference of the rotating drum and produce a layer of material which adheres to its contour and either flow-off out of control or cause blockages.
It is the object of this invention to design an apparatus of the above-discussed type in such manner that materials which will not form drops readily, as well as very fluid materials, can be processed into a granulate in a simple manner and at a high degree of efficiency.